Efficient energy accumulation element for actuators and other devices

ABSTRACT

An efficient energy accumulation element comprising compression spring which uses end caps and flexible rope to pre-compress spring for using in actuators and other devices. The efficient energy accumulation element is independent of external surfaces or end construction of spring. The accumulation and release of energy happens noiselessly.

FIELD OF THE INVENTION

The present invention relates to efficient energy accumulation elementfor actuators and other devices.

OBJECTIVE

The objective is to invent a mechanical energy accumulation elementusing springs which can be prepared for assembly with ease.

Another objective is to invent a mechanical energy accumulation elementusing spring which can be deployed for accumulating higher energy and inwhich the energy accumulation is independent of the assemblyconstruction.

BACKGROUND OF THE INVENTION

Accumulation and release of mechanical energy is a phenomenon deployedin several devices. Springs are one of the commonest elements used forthis purpose. Both compression as well as extension springs are made useof

For using compression springs, pre-compression is the firstpre-requisite. Pre-compression is either achieved by surfaces externalto spring or by constraining the spring modularly. The first method viz.pre-compression by external surfaces requires skillful and timeconsuming assembly.

The second method viz. modular constraining is described, particularlyfor actuators in German patent DE 9314412, a U.S. Pat. No. 8,181,947 andalso in patent Application WO2010/063514. In all these, the minimumlength of cartridge is fixed. So even if the spring can be compressed tothe solid length, the limitation of cartridge design does not allow.Further, these methods cannot be used efficiently for varying diametercompression spring which can be otherwise compressed up to coilthickness.

STATEMENT OF INVENTION

Our invention is the efficient energy accumulation compression springassembled with a flexible yet sturdy rope entangled between two endcaps, each cap being fixed at the respective end of the compressionspring, allowing the springs to compress to any length up to solid. Itis not driven by the stroke needed.

The length of the rope is shorter than compression spring. Thedifference in length is according to the pre-compression or energyaccumulation required. The end caps entrap the hammer or suitably shapedend of the rope. The spring is ready to be deployed without depending onexternal surface construction or even spring end construction.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows the efficient energy accumulation element of progressivelyvarying diameter compression spring in pre-compressed state, ready to beassembled in devices like actuators etc.

FIG. 2 shows the efficient energy accumulation element of constantdiameter compression spring in pre-compressed state, ready to beassembled in devices like actuators etc.

FIG. 3 shows the efficient energy accumulation element in compressedstate, as it becomes during use in the device like actuators etc.

FIG. 4 shows preferred embodiment of construction of end cap.

FIG. 5 shows preferred embodiment of construction of flexible rope.

FIG. 6 shows sectional view of actuator using efficient energyaccumulation element of compression spring.

DETAILED DESCRIPTION OF INVENTION

Preferred embodiment of efficient energy accumulation compression springassembled with a flexible yet sturdy rope will now be described indetail, with reference to the accompanying drawings. The terms andexpressions which have been used here are merely for description and notfor limitation.

Efficient Energy Accumulation Element (10) comprising of compressionspring (5), whether having constant diameter or varying diameter arepre-compressed by using end caps (7, 8) and flexible yet sturdy rope(6). The end caps (7, 8) have diameter (D1) slightly less thancorresponding outer diameter of compression spring (5) so that the endcaps (7, 8) are simply inserted in the spring (5) at the ends.

The end caps (7 or 8) have a through slot (11) through which the hammershaped head (13) of the rope (6) is inserted inside the spring (5) andtaken out from the end cap (7 or 8) at the other end.

The end caps (7 or 8) have another blind slot (12) substantially at 90degrees to through slot (11) in which the hammer shaped head (13) sitswith interference and therefore needs to be pushed in with certaindefinite force such that it cannot come out without using a screw driveror a tool.

The length (16) of the rope (6) is less than length (17) of compressionspring (5).

To assemble Efficient Energy accumulation element (10) with compressionspring (5), the compression spring is required to be held in compressedstate by any simple device like vice, etc. so that its length becomesless than length of rope (16). The first hammer shaped end (13) of therope is inserted from end cap (7) and taken out from the other end cap(8). Hammer shaped ends (13) within both end caps (7) and (8) are turnedso that the hammer shaped end (13) sits over the blind slot (12). Thecompressed spring (5) is then released from the device used for holdingit in compressed state. Due to compression spring (5) trying to regainits uncompressed state, both the hammer shaped ends (13), which were sofar just partially engaged with blind slot (12) now get fully trapped inblind slot (12) due to its interfering construction. The compressionspring remains compressed corresponding to the length difference betweenits free length and the effective length of the rope, as calculated &suited for the application. This is also known as pre-compressed stateof the element (10)

One application described here is actuator (40). When piston (30) movesin direction 31-A, the efficient energy accumulation element (10) ofcompression spring compresses as shown in FIG. 3, and accumulatesenergy. Since rope (6) is flexible as shown in FIG. 3, the extent ofcumulating energy is possible up to solid length of the spring or asmuch as spring permits. The action of accumulating and releasing energyis free from mechanical noise and does not need lubrication as there areno rubbing components.

The construction of through slot (11) and blind slot (12) of end caps(7,8) and ends (13) of flexible rope are possible in several ways suchthat they are assemble-able as described above or in any sequence andtherefore above embodiment is merely a preferred one and not limitingthe invention. “Hammer” shape, in other words, is not a limitation ofthis design but is merely an embodiment and what is important is thatthe contour of the ends of rope and slots in the end caps are such thatthe rope can be passed thru' the end cap (7 or 8) as well as trapped inthe end cap (7 or 8) as required.

Also, the construction of end caps (7, 8) could be such as to entanglewith spring ends for facilitating assembly.

The flexible yet sturdy rope (6) can be of any material so long as it isflexible to allow spring compression without any limitation due toitself

We claim: 01) An efficient energy accumulation element for actuators andother device comprising compression spring and characterized by assemblywith end caps and flexible yet sturdy rope. 02) An efficient energyaccumulation element as claimed in claim 01 wherein the end caps aresuch that the end caps are simply inserted in the compression spring atthe ends or are with entangling construction with the spring ends. 03)An efficient energy accumulation element as claimed in claim 01 whereinthe end caps have through slot and blind slot. 04) An efficient energyaccumulation element as claimed in claim 01 wherein the said flexiblerope has hammer shaped ends. 05) An efficient energy accumulationelement as claimed in claim 01 wherein the said hammer shaped ends passthrough slot and fit tight in blind slot. 06) An efficient energyaccumulation element as claimed in claim 01 wherein relatively, the endshape of the rope and corresponding opening construction in the end capis such as to either pass the end of the rope through the slot orentrap, as required. 07) An efficient energy accumulation element asclaimed in claim 01 wherein the said flexible rope is shorter in lengththan compression spring. 08) An efficient energy accumulation element asclaimed in claim 01 wherein the said flexible rope when assembledthrough end caps keeps the compression spring pre-compressed. 09) Anefficient energy accumulation element as claimed in claim 01 wherein thesaid efficient energy accumulation element is assembled in actuators andother devices. 10) An efficient energy accumulation element as claimedin claim 01 wherein the said efficient energy accumulation element canbe used to accumulate energy up to the limit of the spring. 11) Anefficient energy accumulation element as claimed in claim 01 wherein thesaid efficient energy accumulation element operates without noise andneed of lubrication. 12) An efficient energy accumulation elementsubstantially as hereinabove described in the specification withreference to the accompanying drawings.